OK
not an iceberg at all, but part of a land-based snow slope. In the spring
when the winters snow begins to melt, water flows across the top of
glaciers and snow slopes carrying with it dissolved nutrients in the melt
water. In these conditions, algae grows within the top layer of the ice or
snow catching the goodies as they flow by and taking advantage of the
extra energy from the longer days and stronger sunshine.
In this case the algae is predominantly a red-coloured
species, but further down the slope, green and blue-green colours are discernable.
This is relatively short-lived spring phenomena as soon the very snow and
ice layer that the algae are living in will melt and the algae will flow
down to the sea with the water that provides them with their nourishment.
It is not unusual to see distinctly red, green or blue-green topped ice
bergs in the spring as a result of the growth of such algae.
There are over 300 species of such algae that live in such
harsh and cold conditions. The red colour is a protective chemical
(carotenoids such as astaxanthin) that the alga produces against
exceptionally high concentrations of visible and ultra violet light that
bounces off the snow and ice surfaces and so saturates them to a point where
it become harmful and destructive. Such algae are also found in other parts
of the world, often in high mountains where extra u-v light due to the
thinner atmosphere and again increased light scattering by ice and snow
requires protection by similar pigments.
Sometimes, walking across such an area will leave behind
red footprints as the algae are concentrated by the walker as the snow is
crushed, and sometimes there will be a a faint smell of fresh watermelon
accompanying the phenomena.
Paul
Ward - Pentax equipment, 28mm lens, 35mm film, K64.
This picture may not be copied or used in any manner without
prior written permission.
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